What is the appropriate workup for a patient with a back injury?

Appropriate Workup for Back Injury

The appropriate workup for a back injury should begin with clinical assessment using validated screening criteria, followed by selective imaging based on risk factors, with CT being preferred for suspected fractures and MRI for neurological concerns.

Initial Clinical Assessment

• Perform targeted history focusing on mechanism of injury, pain characteristics, neurological symptoms, and red flag indicators 1
• Apply validated clinical screening criteria:
  • For cervical spine trauma: Use NEXUS or Canadian C-Spine Rule (CCR) criteria to determine need for imaging 1
  • For thoracolumbar injury: Maintain low threshold for imaging in high-energy trauma, elderly patients, or those with osseous demineralization 1

Red Flags Requiring Immediate Advanced Imaging

• Severe or progressive neurological deficits 1
• Suspected cauda equina syndrome (urinary retention, saddle anesthesia) 1, 2
• Suspected spinal infection (fever, immunocompromised state) 1
• Suspected malignancy (history of cancer, unexplained weight loss) 1
• Suspected vertebral fracture in high-risk patients (osteoporosis, steroid use) 1
• Ankylosing spondylitis with trauma (high risk of unstable fractures) 1

Imaging Algorithm

For Acute Traumatic Back Injury:

1. No imaging needed if:

   • Patient meets low-risk criteria by NEXUS or CCR (for cervical spine) 1
   • No red flags present in nonspecific back pain 1

2. CT without contrast is preferred for:

   • Suspected fracture from trauma 1
   • Patients with ankylosing spondylitis with pain after trauma (high risk of unstable fractures) 1
   • Elderly patients with suspected vertebral fracture 1

3. MRI without contrast is indicated for:

   • Suspected spinal cord or nerve root injury 1, 2
   • Suspected disc herniation with persistent symptoms 1, 2
   • Suspected cauda equina syndrome 2
   • Suspected ligamentous injury 1

4. Plain radiography has limited utility but may be appropriate for:

   • Initial screening in low-risk scenarios 1
   • Initial evaluation of possible vertebral compression fracture in selected higher-risk patients 1

Important Considerations

• Avoid unnecessary imaging in nonspecific back pain without red flags, as it does not improve outcomes and may lead to unnecessary interventions 1, 3
• For thoracolumbar trauma, reformatted images from existing chest/abdomen/pelvis CT scans are effective and radiation-dose sparing 1
• The presence of a single vertebral fracture requires assessment of the entire spine due to risk of noncontiguous fractures (up to 20% in high-energy trauma) 1
• MRI findings should be correlated with clinical symptoms, as disc abnormalities are common in asymptomatic patients 2, 3

Special Populations

• For patients >65 years: Standard NEXUS criteria have lower sensitivity (66-89%); consider lower threshold for imaging 1
• For children <16 years: Age-specific criteria should be applied; radiographs are usually appropriate as initial imaging 1
• For patients with ankylosing spondylitis: Maintain high suspicion for fracture even with minor trauma; multiplanar CT is necessary 1

Follow-up Recommendations

• For patients with nonspecific back pain without red flags, imaging can be delayed for at least 1-2 months if symptoms persist 1, 4
• For patients with persistent radicular symptoms despite conservative therapy for 4-6 weeks, consider MRI to evaluate for disc herniation or spinal stenosis 1, 3